Dental implant system

ABSTRACT

The present invention relates to an implant system for teeth, and in particular to an improved implant system for teeth which is capable of enhancing strength of an implant tooth by improving an assembling structure of an implant planted in an alveolar bone, an abutment assembled to the implant and a crown covering the surface of the abutment, and implementing an easier dental operation, so that it is possible to increase a selectable range of operation based on the condition of patient&#39;s teeth.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dental implant system, and inparticular to an improved dental implant system which is capable ofenhancing a strength of a dental implant by improving an assemblingstructure of an implant root planted in an alveolar bone, an abutmentassembled to the implant root and a crown covering the surface of theabutment, and implementing an easier dental operation, so that it ispossible to increase a selectable range of operation based on thecondition of patient's teeth.

2. Description of Related Art

In the dental implant system, an implant root is inserted into analveolar bone and is combined to a bone. Thereafter, an abutment adaptedto support the implant is engaged to the implant root. A crown iscovered onto the abutment. According to the above implant system, it ispossible to independently plant one tooth. In addition, since the thuslyplanted implant has a certain supporting force, it is unnecessary to cuta natural tooth due to the damaged tooth or drawn-out tooth. In othercases, it is possible to stably support a denture. In addition, the lifespan of the same is long, and a physical appearance of the teeth isgood. There are many advantages.

In detail, the implant may be classified into a screw type and anon-screw type.

FIG. 1 is a view illustrating a screw type system which is firstintroduced and is most widely used and has the U.S. Pat. Nos. 4,330,891,4,763,788, 4,824,372, 5,064,375, 5,064,425, 5,069,622, 5,080,589,5,098,293, 5,125,841, 5,145,371, 5,154,612, and 5,269,685.

As shown therein, the screw type implant includes an implant root Iwhich has a self-tapped screw 11 in an outer circumference of the sameand is inserted into and combined with an alveolar bone S, an abutment Awhich is fixed to the implant root I by an abutment screw A1 screwed toan inner circumference of the same, and a crown engagement member Ewhich is engaged to the abutment A by a fixing screw A2 of the crown.

Here, reference character A0 represents an auxiliary screw which seals ascrew hole of the implant root I until the implant root I is combinedwith the alveolar bone S and helps a bone combination of the implantroot in the alveolar bone and prevents an insertion of a debris of food.A dotted line represents a crown C processed and installed, after thealveolar bone and the operated portions are healed up.

The above screw type implant system needs lots of parts, so that thefabrication and maintenance costs are expensive, and an operation iscomplicated. Therefore, a complication may be developed. In addition,the medical care insurance rate of the patient may be increased.

In particular, the above system is implemented based on an engagingforce of the screws A1 and A2 between the parts, the maximum externalforce such as a uniting force, etc. is determined based on the size ofthe width of the screw thread and the width and length of the implant.Therefore, the supporting force is small. In case that the supportingforce is not bearable, the screws may be loosened.

In addition, the dental implant system in the screw type may beresistant to the compressing force when a uniting function is performedin the mouth. However, when the tension force is increased, the screwsmay be loosened during the use of the implant.

In addition, a certain gap between the implant root and abutment isformed by a poor interconnection between the implant root and abutment,whereby a certain bacteria may invade thereto to cause a sanitationproblem and an inflammation in a surrounding tissue, so that an alveolarbone may be absorbed.

FIG. 2 is a view illustrating the dental implant system of the non-screwtype which is invented to overcome the problems of the screw typeimplant system. As shown therein, there is provided a locking tapermethod which is implemented based on a surface friction force withrespect to the engagement between parts.

The constitution of FIG. 2 is a representative in the locking tapermethod which is commercially available of “Bicon”.

In the constitution of the above system, a well I2 having the taperedsurfaces which are expanded in an upper direction is formed in theinterior of the implant I inserted into the alveolar bone S, and a postportion A3 having a certain taper corresponding thereto is extended in alower portion of the abutment A. Namely, the abutment A is engaged tothe implant I based on a surface friction force between the well I2 andthe post portion A3.

An expanding flare portion A4 is provided in an upper portion of theabutment A, and both sides of the same are cut into provide a conicalhead forming a slanted surface A5.

In the above conventional dental implant system, the engaging operationwith respect to the alveolar bone S is implemented by the dental implantsystem I, and the abutment A supporting the crown C is engaged to theimplant root I.

However, since an external force such as a uniting force is applied tothe abutment A through the crown C, the strength of the above system isdetermined based an engaging force between the abutment A and implantroot I and the strength of the implant root I itself.

When compared with the screw type of FIG. 1 in which the engagement isimplemented based on the screw treads of screws A1 and A2 which haverelatively smaller diameters, the locking taper method of FIG. 2 hasmuch higher engaging forces, and it has a screw loosening problem.However, since the maximum strength is determined based on the minimumdiameter of the engaging part, there is a big problem in that point.

Namely, when assembling the implant root I to the abutment A, the postportion A3 of the abutment A is inserted into the well I2 formed in thecenter of the implant root I. Therefore, the size “a” of the neckportion of the post portion A3 and the size “b” of the surroundingportion of the implant root I which size is obtained by subtracting thesize of the neck portion are too small as shown in FIG. 3.

Therefore, a breaking problem may occur in case of the teeth requiring alarger uniting force such as back tooth,. The above problem may be mostcritical to the conventional implant system. So, it is most needed toovercome the above problem.

In particular, after being implanted, the minimum diameter of thesurrounding cave of the implant is preferably about 2.0 mm. Therefore,in case of the constitution in FIG. 2, the minimum diameter should be7.5 mm. The relatively small portion needs a small implant. The size ofthe neck portion of the post portion of FIG. 2 should be over 2.0 mm notto be easily broken. In the above conventional method, the actual use ofthe implant is limited due to the impossibility to decrease the size ofthe implant, In addition, if the size of the implant is much smaller,the implant may be easily broken. Therefore, there are many problems foractually using the same.

In the conventional implant of FIGS. 1 trough 3, the upper portion andlower portion of the implant root may not be formed at a certain angletherebetween.

Namely, when planting the implant root into the alveolar bone, it may benecessary to avoid an anatomical structure(cortex which forms a loweralveolar pipe, biperforate, and maxillary sinus) of a maxilla ormandible under a certain circumstance. In order to avoid the aboveanatomical structure, an implant root bent at a certain angle isnecessary. However, since the conventional implant root has a well inthe center of the same, it is impossible to form a bent type implant.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides a dental implant system inorder to overcomes the problems encountered in the conventional art.

It is an object of the present invention to provide a dental implantsystem which is capable of forming a post portion in an implant root anda well in an abutment as the locking taper method instead of aconventional art in which a well is formed in an implant root and a postportion is formed in an abutment, so that when engaging the same, it ispossible to implement a stable engagement, fabricate a smaller size ofthe implant root, and plant the implant with avoiding an anatomicalstructure in the mouth.

To achieve the above object, In a dental implant system which includesan implant root 10 planted in an alveolar bone, an abutment 20 assembledto the implant root, and a crown 30 assembled to the abutment, thedental implant system in which:

-   -   the implant root 10 is formed in a cylindrical shape without a        longitudinal well in the interior of the same, and comprises a        circular rim groove 13 formed along an outer circumferential        surface of an upper portion of the same, a post portion 11        having a first taper portion 14 and a second taper portion 15        below the circular rim groove 13, and a planting portion 12 and        multiple protruded circular plate pins 12 below the post        portion11; and    -   the abutment 20 is formed in a cylindrical shape having an        expanded portion 21 curved at middle of the same, and comprises        a well 23 including a taper inner diameter potion 22 in the        lower surface of the same, so that the post portion 11 of the        implant 10 is inserted into the well 23, a crown engaging potion        25 including the expanded portion 21 in the upper side, and an        engaging well 24 in an upper surface of the engaging portion;        and    -   the crown 30 is engaged to an upper side of the abutment and        comprises an abutment post 31 corresponding to the engaging well        24 at a center portion of the interior of the crown.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become better understood with reference tothe accompanying drawings which are given only by way of illustrationand thus are not limitative of the present invention, wherein;

FIG. 1 is a cross-sectional view illustrating an example of an assembledstate of a conventional dental implant system;

FIG. 2 is a cross-sectional view illustrating another example of anassembled state of a conventional tooth implant system;

FIG. 3 is a disassembled cross-sectional view of FIG. 2;

FIG. 4 is a cross-sectional view illustrating an assembled state of adental implant system according to the present invention;

FIG. 5 is a cross-sectional view illustrating a disassembled state of adental implant system according to the present invention;

FIG. 6 is a view illustrating another embodiment of an implant accordingto the present invention; and

FIG. 7 is a view illustrating another embodiment of an abutmentaccording to the present invention.

DESCRIPTIONS OF THE MAJOR ELEMENTS IN THE DRAWINGS

-   -   10: implant root    -   20: abutment    -   30: crown

DETAILED DESCRIPTION OF PREFFERED EMBODIMENTS

The preferred embodiments of the present invention will be describedwith reference to the accompanying drawings.

FIG. 4 is a cross-sectional view illustrating an assembled state of animplant system according to the present invention, and FIG. 5 is a viewillustrating a disassembled state of an implant according to the presentinvention.

As shown therein, the implant according to the present inventionincludes an implant root 10 and an abutment 20.

In a dental implant system which includes an implant root 10 planted inan alveolar bone, an abutment 20 assembled to the implant root, and acrown 30 assembled to the abutment, the dental implant system in which:

-   -   the implant root 10 is formed in a cylindrical shape without a        longitudinal well in the interior of the same, and comprises a        circular rim groove 13 formed along an outer circumferential        surface of an upper portion of the same, a post portion 11        having a first taper portion 14 and a second taper portion 15        below the circular rim groove 13, and a planting portion 12 and        multiple protruded circular plate pins 12 below the post        portion11; and    -   the abutment 20 is formed in a cylindrical shape having an        expanded portion 21 curved at middle of the same, and comprises        a well 23 including a taper inner diameter potion 22 in the        lower surface of the same, so that the post portion 11 of the        implant 10 is inserted into the well 23, a crown engaging potion        25 including the expanded portion 21 in the upper side, and an        engaging well 24 in an upper surface of the engaging portion21.

FIG. 5 is a view illustrating an embodiment of the implant root 10according to the present invention.

As shown in FIG. 5, in the implant root 10, the minimum diameter of theupper most portion of the post portion 11 is about 2 mm, and the heightof the same is about 3.5 mm, and in the planting portion 12, the maximumdiameter of the upper most circular plate pin 16 is about 4 mm, theheight of the same is about 8 mm, and the call size of the same is 4*8.

There are about 7˜8 call sizes from the relatively smaller sizes to thebigger sizes.

The circular rim groove 13 of the post portion 11 is formed in a portionlower from the upper surface by 0.5 mm, and has a width of about 0.3 mmand a depth of about 0.3 mm.

The circular rim groove 13 is adapted to prevent any escape of theimplant due to a certain friction force when the abutment 20 isassembled.

The first taper portion 14 of the post portion 11 has a slant of about1.50. Namely, the diameter of the upper most portion in which thecircular rim groove 13 is formed has the smallest size, and the size ofthe same is gradually increased torward the lower direction. When theminimum size of the upper most portion is about 2 mm, the diameter justbefore the second taper portion 15 is about 2.183 mm.

The second taper portion 15 has about 0.5 mm height from the first taperportion, and has a slant of about 3°, so that it is possible toimplement a tight insertion when it is inserted into the well 23 of theabutment.

There are provided seven circular plate pins 16 of the planting portion12. The first circular plate pin 16 a of the upper most portion has aheight of 1.3 mm, and a diameter of 4 mm, and the distance from the nextsecond circular plate pin 16 b to the seventh circular plate pin 16 g is1.1 mm.

In addition, the maximum diameters from the first circular plate pin 16a to the fourth circular plate pin 16 d are same, and the diameters aregradually decreased in the directions of the fifth circular plate pin 16e through the seventh circular plate pin 16 g in order for the teeth tohave a natural physical appearance. The diameter of the seventh circularplate pin 16 of the lower most portion is about 3 mm.

The upper surface of the first circular plate pin 16 a has a slantsurface of about 45° in an opened umbrella shape, and the secondcircular plate pin 16 b through the seventh circular plate pin 16 g alsohave the opened umbrella shapes, and the upper surfaces of the same havea slant surface of about 20°.

In addition, a protrusion 17 is formed in a lower surface of the seventhcircular plate pin 16 g of the lower most portion. The protrusion 17 isadapted to eliminate an unnecessary alveolar bone removing work bycoinciding an end blade portion of a reamer used for forming a well inthe alveolar bone for the implant with the protrusion 17.

It is important to fabricate the implant root 10 according to thepresent invention in such a manner that the post portion 11 is slantedat a certain angle from the planting portion 12(in the conventional art,it is impossible to fabricate the implant bent at a certain angle due toa certain well in the interior of the same).

The physical appearances of the post portion 11 and the planting portion12 are the same as the above earlier embodiment of the presentinvention. As shown in FIG. 6, the post portion 11 is preferably slantedat about 10°˜20° with respect to the planting portion 12.

In this case, even when the planting portion 12 is planted in a slantedstate, the post portion 11 maintains a vertical state by avoiding thecortex bone formed of a lower alveolar pipe, biperforate, and maxilla inthe major anatomical structure.

In addition, FIG. 5 is a view illustrating an embodiment of the abutment20 according to the present invention, and there may be many abutmentshaving different sizes and other physical appearances.

The abutment 20 is formed in a cylindrical shape having an expandedportion 21 curved at middle of the same, and comprises a well 23including a taper inner diameter potion 22 in the lower surface of thesame, so that the post portion 11 of the implant 10 is inserted into thewell 23, a crown engaging potion 25 including the expanded portion 21 inthe upper side, and an engaging well 24 in an upper surface of theengaging portion.

The taper angle of the inner diameter portion 22 into which the postportion 11 is inserted has an angle of about 1.5° in order for theabutment 20 to be used for the implant root 10.

The crown is engaged to the upper portion of the expanding portion 21,and an inner circumferential diameter portion of the well 23 issurface-processed for preventing any acid corrosion.

Therefore, when being engaged with the post portion of the implant, thelower most portion of the abutment is connected to the inner portion ofthe alveolar bone together with the post portion of the implant, so thatit is possible to implement the maximum bone engagement therebypreventing an absorption of the alveolar bone.

When the well 23 formed in the lower portion of the abutment 20 isengaged with the post portion 11 of the implant root 10, the minimumdiameter is the diameter of the lower portion of the abutment. Sincethis diameter is larger than that of the conventional abutment, it ispossible to implement a better physical appearance when covering thecrown.

For example, since in recovery of the front tooth portion of themaxilla, the thickness of the lower portion of the exposed portion in anatural tooth is more than about 7.0 mm, it is preferred that thethickness of the tooth diameter portions of the crown must be similar tothe thickness of the lower portion of the exposed portion of the naturalteeth after connecting the lower and upper implants in order to adapt anatural tooth shape. In the abutment according to the present invention,it is possible to implement a certain tooth diameter portion verysimilar to the natural teeth since the lower portion of the abutment isthicker than that of the conventional abutment.

FIG. 7 is a view illustrating the abutment 20 according to the presentinvention.

As shown therein, an engaging well 24 is formed in an upper surface ofthe crown engaging portion 25 thereby implementing an easier engagementof the crown 30.

At this time, since the engaging well 24 is engaged according to thelocking taper method, it is preferred to form a taper in the innerdiameter portion having a slant of about 1.5°.

The post portion 31 of the abutment inserted into the engaging well 24is adapted to engage the Resin crown for a path and synthetic resin ofthe crown. It is possible to prevent any escape of the crown based onthe engaging well 24 without using a permanent cement. Therefore, in thepresent invention does not need to use a dental cement.

As described above, in the present invention, the post portion havingthe first taper portion and second taper portion is formed in the upperportion of the implant root compared to the conventional art in whichthe well is formed in the implant root, and the post portion is formedin the abutment. In addition, a well having a tapered inner diameterportion is formed in the lower surface of the abutment and implements astable assembled state thereby providing an excellent support strength,decreasing the minimum diameter of the implant root, and bending thepost portion at a certain angle with respect to the planting portion.

Since the abutment is assembled in such a manner that the outer diameterportion of the post portion is surrounded, the thickness of the toothdiameter portion is large, so that it is possible to implement a certaintooth diameter portion which is the same as the tooth diameter portionof the natural teeth. Furthermore, since an engaging well according tothe locking taper method is provided for the engagement of the crown inthe upper portion, it is possible to implement an easier assembling ofthe crown. Also, the present invention does not need to use the dentalcement.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described examples are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the meets and bounds of theclaims, or equivalences of such meets and bounds are therefore intendedto be embraced by the appended claims.

1. In a dental implant system which includes an implant root planted inan alveolar bone, an abutment assembled to the implant root, and a crownassembled to the abutment, the dental implant system in which: theimplant root is formed in a cylindrical shape without a longitudinalwell in the interior of the same, and comprises a circular rim grooveformed along an outer circumferential surface of an upper portion of thesame, a post portion having a first taper portion and a second taperportion below the circular rim groove, and a planting portion andmultiple protruded circular plate pins below the post portion; and theabutment is formed in a cylindrical shape having an expanded portioncurved at middle of the same, and comprises a well including a taperinner diameter potion in the lower surface of the same, so that the postportion of the implant is inserted into the well, a crown engagingpotion including the expanded portion in the upper side, and an engagingwell in an upper surface of the engaging portion; and the crown isengaged to an upper side of the abutment and comprises an abutment postcorresponding to the engaging well at a center portion of the interiorof the crown.
 2. The dental implant system of claim 1, wherein the firsttaper portion of the implant root and the taper inner diameter portionof the abutment have a taper having an angle of about 0.5°˜2.5° withrespect to a center line of the cylindrical shape.
 3. The dental implantsystem of claim 1, wherein the center portion in the said post portionof the implant root is formed at an angle of about 10°˜20° with respectto the center of the planting portion.
 4. The dental implant system ofclaim 1, wherein the abutment includes an engaging well which engagesthe abutment post of the crown in the upper surface of the same.
 5. Thedental implant system of claim 4, wherein the engaging well of theabutment and the outer circumferential surface of the abutment post havea taper of an angle of about 0.5°˜2.5° with respect to the center lineof the cylindrical shape.